A media file may include one or more media tracks (e.g., an audio track, a video track, a text track, or a data track) that each represent media content (e.g., audio, video, captions, or commentary). For example, an audio file for a song recorded in stereo may store one audio track for left channel audio and another audio track for right channel audio. As another example, a video file for a movie with multiple soundtracks may store many media tracks, such as, high definition video track, a standard definition video track, a set of audio tracks for musical score (e.g., left stereo channel and right stereo channel), another set of audio tracks for sound effects (e.g., left front surround channel, center front surround channel, right front surround channel, left rear surround channel, right rear surround channel, and subwoofer channel), yet another set of audio tracks for dialogue in English (e.g., five surround channels), a further set of audio tracks for dialogue in French (e.g., five surround channels), and a text track for closed captions.
Media files may be stored by a user in a data repository as a media library (e.g., media collection) of the user. In some cases, the user is authorized to play a media file and its media tracks (e.g., by creating the media tracks stored in the media file, purchasing the media file and its media tracks, or otherwise being authorized to play the media file). In other cases, the user is not authorized to play the media file or any of its media tracks.